Acute Mycoplasma hyopneumoniae infection in a naive breed-to-wean herd

Mycoplasma hyopneumoniae (MHP) infection occurs globally and contributes to economic losses. Acute infections occur in immunologically naive populations affecting pigs of all ages and causing clinical signs including fever, coughing, acute respiratory distress, and death. An acute MHP infection was investigated in a naive 4200-sow breed-to-wean herd. An increase in sow mortality (4.16%, 8.33%, and 3.89%) and preweaning mortality (10.45%, 12.38%, and 12.06%) occurred when comparing the naive, acute infection, and post-infection periods, respectively. Further production differences included 166.3, 158.3, and 164.2 kg weaned/sow/year and 29.43, 28.35, and 28.28 pigs weaned/mated female/year in naive, acute infection, and post-infection periods, respectively.